How to bind a function pointer in a struct?

I created a small example to learn how to do it.


Using cigloo I generated extern declaration and pasted
inside a bigloo module. Is there a way to include the
output of cigloo inside the module without copy/pasting?

Here is the content of main.scm:

(module foo
     (extern
      ;; beginning of example.h
      (create_abc::ABC* () "create_abc")
      (sum::int (int int) "sum")
      (type s-ABC_ (struct (value::int "value") 
(sum::*int,int,string->int "sum")) "struct ABC_")
      (type int,int,string->int "int ($(int,int,char *))")
      (type *int,int,string->int (function int (int int string)) "int 
((*$)(int,int,char *))")
      (type ABC s-ABC_ "ABC")
      (type ->ABC* "ABC *($())")
      (type int,int->int "int ($(int,int))")
      ;; end of example.h
      )
   (main main))

(define (main x)
   (let ((out (create_abc)))
     (print "total:")
     (print out)))


When I run the command: bigloo main.scm libexample.so -o main

I get the following error:

main.c:19:8: error: unknown type name ‘ABC’
  extern ABC * create_abc();

What I am doing wrong?

#include <stdlib.h>
#include <stdio.h>

#include "example.h"


int bar(int a, int b, char * message) {
  printf("%s\n", message);
  return a + b + 40;
}

ABC * create_abc() {
  ABC * my_struct = malloc(sizeof(ABC));
  my_struct->value = 42;
  my_struct->sum = bar;
  return my_struct;
}

int sum(int a, int b) {
  return a + b;
}

typedef struct ABC_ {
  int value;
  int (*sum)(int a, int b, char * message);
} ABC;

ABC * create_abc();

int sum(int a, int b);